Fix build failures due to autoconf and automake; fix compiler warning
Three commits to fix respectively, autoconf, automake, and a compiler warning. Result is now:
make check-TESTS
make[3]: Entering directory '/srv/NAS/Sunny/SourceCode/gross/src'
make[4]: Entering directory '/srv/NAS/Sunny/SourceCode/gross/src'
PASS: sha256
PASS: revaddr
PASS: mask
PASS: msgqueue
PASS: bloom
============================================================================
Testsuite summary for gross 1.0-svn
============================================================================
# TOTAL: 5
# PASS: 5
# SKIP: 0
# XFAIL: 0
# FAIL: 0
# XPASS: 0
# ERROR: 0
============================================================================